Even Skip Gates's Self-Justification contains a lie--about Mrs Affleck as a Freedom Rider.

Gates released a statement defending the decision, which is below in full:

The mission of “Finding Your Roots” is to find and share interesting stories from our celebrity guests’ ancestries and use those stories to unlock new ways to learn about our past. We are very grateful to all of our guests for allowing us into their personal lives and have told hundreds of stories in this series including many about slave ancestors—never shying away from chapters of a family’s past that might be unpleasant.
Ultimately, I maintain editorial control on all of my projects and, with my producers, decide what will make for the most compelling program. In the case of Mr. Affleck — we focused on what we felt were the most interesting aspects of his ancestry—including a Revolutionary War ancestor, a 3rd great–grandfather who was an occult enthusiast, and his mother who marched for Civil Rights during the Freedom Summer of 1964.

SOURCE: The New York Daily News | PBS